Investigation of temperature profile and temperature stability of micro diffusion flame under the influence of magnetic field by use of a holo-shear lens-based interferometer

Abstract

Holo-shear lens-based interferometer is demonstrated to study the influence of gradient magnetic fields (i.e., upward decreasing and upward increasing) and uniform magnetic field on the temperature and temperature profile of a wick stabilized micro diffusion flame created from the candle. Sheared interferograms in the absence and presence of microflame are captured using CCD camera. Fourier fringe analysis method is used to extract the phase-gradient information of ambient air without flame and heated air of microflame separately. The phase difference map of microflame and ambient air is used for the extraction of refractive index difference and temperature distribution inside the microflame. The experimental investigations reveal that temperature and temperature stability of the microflame increase in the upward decreasing and uniform magnetic field, while the temperature and temperature stability inside the microflame decrease in upward increasing magnetic field in comparison to temperature inside the microflame in the absence of magnetic field. Increment in the temperature of the microflame in uniform magnetic field is contrary to macro diffusion flame, where there is a negligible influence on the temperature in uniform magnetic field. Holo-shear lens-based interferometer is simple, lightweight, easy to implement, less vibration-sensitive, and can cover microflame to macroflame under investigation.